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path: root/drivers/watchdog/it87_wdt.c
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Diffstat (limited to 'drivers/watchdog/it87_wdt.c')
-rw-r--r--drivers/watchdog/it87_wdt.c168
1 files changed, 90 insertions, 78 deletions
diff --git a/drivers/watchdog/it87_wdt.c b/drivers/watchdog/it87_wdt.c
index b1bc72f9a209..a2d9a1266a23 100644
--- a/drivers/watchdog/it87_wdt.c
+++ b/drivers/watchdog/it87_wdt.c
@@ -137,7 +137,6 @@
static unsigned int base, gpact, ciract, max_units, chip_type;
static unsigned long wdt_status;
-static DEFINE_SPINLOCK(spinlock);
static int nogameport = DEFAULT_NOGAMEPORT;
static int exclusive = DEFAULT_EXCLUSIVE;
@@ -163,18 +162,26 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started, default="
/* Superio Chip */
-static inline void superio_enter(void)
+static inline int superio_enter(void)
{
+ /*
+ * Try to reserve REG and REG + 1 for exclusive access.
+ */
+ if (!request_muxed_region(REG, 2, WATCHDOG_NAME))
+ return -EBUSY;
+
outb(0x87, REG);
outb(0x01, REG);
outb(0x55, REG);
outb(0x55, REG);
+ return 0;
}
static inline void superio_exit(void)
{
outb(0x02, REG);
outb(0x02, VAL);
+ release_region(REG, 2);
}
static inline void superio_select(int ldn)
@@ -255,12 +262,11 @@ static void wdt_keepalive(void)
set_bit(WDTS_KEEPALIVE, &wdt_status);
}
-static void wdt_start(void)
+static int wdt_start(void)
{
- unsigned long flags;
-
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
+ int ret = superio_enter();
+ if (ret)
+ return ret;
superio_select(GPIO);
if (test_bit(WDTS_USE_GP, &wdt_status))
@@ -270,15 +276,15 @@ static void wdt_start(void)
wdt_update_timeout();
superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
+
+ return 0;
}
-static void wdt_stop(void)
+static int wdt_stop(void)
{
- unsigned long flags;
-
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
+ int ret = superio_enter();
+ if (ret)
+ return ret;
superio_select(GPIO);
superio_outb(0x00, WDTCTRL);
@@ -288,7 +294,7 @@ static void wdt_stop(void)
superio_outb(0x00, WDTVALMSB);
superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
+ return 0;
}
/**
@@ -303,8 +309,6 @@ static void wdt_stop(void)
static int wdt_set_timeout(int t)
{
- unsigned long flags;
-
if (t < 1 || t > max_units * 60)
return -EINVAL;
@@ -313,14 +317,15 @@ static int wdt_set_timeout(int t)
else
timeout = t;
- spin_lock_irqsave(&spinlock, flags);
if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
- superio_enter();
+ int ret = superio_enter();
+ if (ret)
+ return ret;
+
superio_select(GPIO);
wdt_update_timeout();
superio_exit();
}
- spin_unlock_irqrestore(&spinlock, flags);
return 0;
}
@@ -339,12 +344,12 @@ static int wdt_set_timeout(int t)
static int wdt_get_status(int *status)
{
- unsigned long flags;
-
*status = 0;
if (testmode) {
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
+ int ret = superio_enter();
+ if (ret)
+ return ret;
+
superio_select(GPIO);
if (superio_inb(WDTCTRL) & WDT_ZERO) {
superio_outb(0x00, WDTCTRL);
@@ -353,7 +358,6 @@ static int wdt_get_status(int *status)
}
superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
}
if (test_and_clear_bit(WDTS_KEEPALIVE, &wdt_status))
*status |= WDIOF_KEEPALIVEPING;
@@ -379,9 +383,17 @@ static int wdt_open(struct inode *inode, struct file *file)
if (exclusive && test_and_set_bit(WDTS_DEV_OPEN, &wdt_status))
return -EBUSY;
if (!test_and_set_bit(WDTS_TIMER_RUN, &wdt_status)) {
+ int ret;
if (nowayout && !test_and_set_bit(WDTS_LOCKED, &wdt_status))
__module_get(THIS_MODULE);
- wdt_start();
+
+ ret = wdt_start();
+ if (ret) {
+ clear_bit(WDTS_LOCKED, &wdt_status);
+ clear_bit(WDTS_TIMER_RUN, &wdt_status);
+ clear_bit(WDTS_DEV_OPEN, &wdt_status);
+ return ret;
+ }
}
return nonseekable_open(inode, file);
}
@@ -403,7 +415,16 @@ static int wdt_release(struct inode *inode, struct file *file)
{
if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
if (test_and_clear_bit(WDTS_EXPECTED, &wdt_status)) {
- wdt_stop();
+ int ret = wdt_stop();
+ if (ret) {
+ /*
+ * Stop failed. Just keep the watchdog alive
+ * and hope nothing bad happens.
+ */
+ set_bit(WDTS_EXPECTED, &wdt_status);
+ wdt_keepalive();
+ return ret;
+ }
clear_bit(WDTS_TIMER_RUN, &wdt_status);
} else {
wdt_keepalive();
@@ -484,7 +505,9 @@ static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
&ident, sizeof(ident)) ? -EFAULT : 0;
case WDIOC_GETSTATUS:
- wdt_get_status(&status);
+ rc = wdt_get_status(&status);
+ if (rc)
+ return rc;
return put_user(status, uarg.i);
case WDIOC_GETBOOTSTATUS:
@@ -500,14 +523,22 @@ static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
switch (new_options) {
case WDIOS_DISABLECARD:
- if (test_bit(WDTS_TIMER_RUN, &wdt_status))
- wdt_stop();
+ if (test_bit(WDTS_TIMER_RUN, &wdt_status)) {
+ rc = wdt_stop();
+ if (rc)
+ return rc;
+ }
clear_bit(WDTS_TIMER_RUN, &wdt_status);
return 0;
case WDIOS_ENABLECARD:
- if (!test_and_set_bit(WDTS_TIMER_RUN, &wdt_status))
- wdt_start();
+ if (!test_and_set_bit(WDTS_TIMER_RUN, &wdt_status)) {
+ rc = wdt_start();
+ if (rc) {
+ clear_bit(WDTS_TIMER_RUN, &wdt_status);
+ return rc;
+ }
+ }
return 0;
default:
@@ -560,16 +591,17 @@ static int __init it87_wdt_init(void)
int rc = 0;
int try_gameport = !nogameport;
u8 chip_rev;
- unsigned long flags;
+ int gp_rreq_fail = 0;
wdt_status = 0;
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
+ rc = superio_enter();
+ if (rc)
+ return rc;
+
chip_type = superio_inw(CHIPID);
chip_rev = superio_inb(CHIPREV) & 0x0f;
superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
switch (chip_type) {
case IT8702_ID:
@@ -603,8 +635,9 @@ static int __init it87_wdt_init(void)
return -ENODEV;
}
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
+ rc = superio_enter();
+ if (rc)
+ return rc;
superio_select(GPIO);
superio_outb(WDT_TOV1, WDTCFG);
@@ -620,21 +653,16 @@ static int __init it87_wdt_init(void)
}
gpact = superio_inb(ACTREG);
superio_outb(0x01, ACTREG);
- superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
if (request_region(base, 1, WATCHDOG_NAME))
set_bit(WDTS_USE_GP, &wdt_status);
else
- rc = -EIO;
- } else {
- superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
+ gp_rreq_fail = 1;
}
/* If we haven't Gameport support, try to get CIR support */
if (!test_bit(WDTS_USE_GP, &wdt_status)) {
if (!request_region(CIR_BASE, 8, WATCHDOG_NAME)) {
- if (rc == -EIO)
+ if (gp_rreq_fail)
printk(KERN_ERR PFX
"I/O Address 0x%04x and 0x%04x"
" already in use\n", base, CIR_BASE);
@@ -646,21 +674,16 @@ static int __init it87_wdt_init(void)
goto err_out;
}
base = CIR_BASE;
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
superio_select(CIR);
superio_outw(base, BASEREG);
superio_outb(0x00, CIR_ILS);
ciract = superio_inb(ACTREG);
superio_outb(0x01, ACTREG);
- if (rc == -EIO) {
+ if (gp_rreq_fail) {
superio_select(GAMEPORT);
superio_outb(gpact, ACTREG);
}
-
- superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
}
if (timeout < 1 || timeout > max_units * 60) {
@@ -704,6 +727,7 @@ static int __init it87_wdt_init(void)
"nogameport=%d)\n", chip_type, chip_rev, timeout,
nowayout, testmode, exclusive, nogameport);
+ superio_exit();
return 0;
err_out_reboot:
@@ -711,49 +735,37 @@ err_out_reboot:
err_out_region:
release_region(base, test_bit(WDTS_USE_GP, &wdt_status) ? 1 : 8);
if (!test_bit(WDTS_USE_GP, &wdt_status)) {
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
superio_select(CIR);
superio_outb(ciract, ACTREG);
- superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
}
err_out:
if (try_gameport) {
- spin_lock_irqsave(&spinlock, flags);
- superio_enter();
superio_select(GAMEPORT);
superio_outb(gpact, ACTREG);
- superio_exit();
- spin_unlock_irqrestore(&spinlock, flags);
}
+ superio_exit();
return rc;
}
static void __exit it87_wdt_exit(void)
{
- unsigned long flags;
- int nolock;
-
- nolock = !spin_trylock_irqsave(&spinlock, flags);
- superio_enter();
- superio_select(GPIO);
- superio_outb(0x00, WDTCTRL);
- superio_outb(0x00, WDTCFG);
- superio_outb(0x00, WDTVALLSB);
- if (max_units > 255)
- superio_outb(0x00, WDTVALMSB);
- if (test_bit(WDTS_USE_GP, &wdt_status)) {
- superio_select(GAMEPORT);
- superio_outb(gpact, ACTREG);
- } else {
- superio_select(CIR);
- superio_outb(ciract, ACTREG);
+ if (superio_enter() == 0) {
+ superio_select(GPIO);
+ superio_outb(0x00, WDTCTRL);
+ superio_outb(0x00, WDTCFG);
+ superio_outb(0x00, WDTVALLSB);
+ if (max_units > 255)
+ superio_outb(0x00, WDTVALMSB);
+ if (test_bit(WDTS_USE_GP, &wdt_status)) {
+ superio_select(GAMEPORT);
+ superio_outb(gpact, ACTREG);
+ } else {
+ superio_select(CIR);
+ superio_outb(ciract, ACTREG);
+ }
+ superio_exit();
}
- superio_exit();
- if (!nolock)
- spin_unlock_irqrestore(&spinlock, flags);
misc_deregister(&wdt_miscdev);
unregister_reboot_notifier(&wdt_notifier);
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-16 12:29:12 +0300